passwordEncryptionCodec doesn't work in 3.3

In Grails 3.2.x, you can use an encoded password for data source if you set `passwordEncryptionCodec` in configuration file like this:

```yml
// in application.yml
dataSource:
pooled: true
jmxExport: true
driverClassName: org.h2.Driver
username: sa
#password: password
password: PASSWORD
passwordEncryptionCodec: UppercaseCodec
# See https://github.com/nobeans/grails-issues/blob/master/g3211-passwordEncryptionCodec/grails-app/utils/UppercaseCodec.groovy
```

But a code for this feature was removed at 457b5412f0739d9acb7773f896ab319b68a32c63 (commented as "Use the DataSourceConnectionSourceFactory to create the datasources").
In the commit, the code using `passwordEncryptionCodec` in `DataSourceGrailsPlugin` was replaced with a code just using `org.grails.datastore.gorm.jdbc.connections.DataSourceConnectionSourceFactory`.

### Task List

- [x] Steps to reproduce provided
- [ ] Stacktrace (if present) provided
- [x] Example that reproduces the problem uploaded to Github
- [x] Full description of the issue provided (see below)

### Steps to Reproduce

1. Implement your Codec class (like `UppercaseCodec`.)
2. Configure to use `passwordEncryptionCodec` in `application.yml`.
3. Run the application.
4. Access to `http://localhost:8080/dbconsole/`.
5. Input the word `password` (lower-case) in `Password` field.
6. Click `Test Connection` button.

### Expected Behaviour

The message `Test successful` is shown in the bottom.

### Actual Behaviour

The error message `Wrong user name or password [28000-195] 28000/28000` is shown in the bottom.
If you use the word `PASSWORD` (upper-case), you can see the message `Test successful`.

### Environment Information

- **Operating System**: macOS 10.12.5
- **Grails Version**: 3.3.0.RC1
- **JDK Version**: 1.8.0_131

### Example Application

- In Grails 3.2.11, it works well expectedly: https://github.com/nobeans/grails-issues/tree/master/g3211-passwordEncryptionCodec
- In Grails 3.3.0.RC1, nothing occurs: https://github.com/nobeans/grails-issues/tree/b6c2151/g330rc1-passwordEncryptionCodec

Start by comparing the password handling in DataSourceGrailsPlugin before and after the referenced change to DataSourceConnectionSourceFactory. Run the linked Grails 3.3.0.RC1 example with passwordEncryptionCodec configured, then verify that entering the unencoded password succeeds in the dbconsole as it does in the Grails 3.2.11 example.

Written by the indexing model from the issue text.